perf: import some things later

Saves on startup time

dvc/remote/http.py

@@ -3,7 +3,6 @@ from __future__ import unicode_literals
 from dvc.scheme import Schemes
 from dvc.utils.compat import open
 
-import requests
 import logging
 
 from dvc.progress import Tqdm
@@ -79,6 +78,8 @@ class RemoteHTTP(RemoteBASE):
         return etag
 
     def _request(self, method, url, **kwargs):
+        import requests
+
         kwargs.setdefault("allow_redirects", True)
         kwargs.setdefault("timeout", self.REQUEST_TIMEOUT)
 

dvc/remote/ssh/__init__.py

@@ -24,9 +24,6 @@ from dvc.scheme import Schemes
 from dvc.remote.pool import get_connection
 from dvc.progress import Tqdm
 
-from .connection import SSHConnection
-
-
 logger = logging.getLogger(__name__)
 
 
@@ -139,6 +136,8 @@ class RemoteSSH(RemoteBASE):
                     )
                 self.password = password
 
+        from .connection import SSHConnection
+
         return get_connection(
             SSHConnection,
             host,

dvc/updater.py

@@ -4,7 +4,6 @@ import sys
 import os
 import time
 import logging
-import requests
 import colorama
 from pkg_resources import parse_version
 
@@ -82,6 +81,7 @@ class Updater(object):  # pragma: no cover
 
     def _get_latest_version(self):
         import json
+        import requests
 
         try:
             r = requests.get(self.URL, timeout=self.TIMEOUT_GET)

dvc/utils/http.py

@@ -1,8 +1,6 @@
 from contextlib import contextmanager
 import io
 
-import requests
-
 from dvc.utils.compat import FileNotFoundError
 
 
@@ -28,6 +26,7 @@ def open_url(url, mode="r", encoding=None):
 @contextmanager
 def iter_url(url, chunk_size=io.DEFAULT_BUFFER_SIZE):
     """Iterate over chunks requested from url."""
+    import requests
 
     def request(headers=None):
         the_url = url() if callable(url) else url